Process of making printing plates



May 15, 1928. r 1,669,821

7 A. GRASS PROCESS OF MAKING PRINTING PLATES Original Filed May 31.1.921

Fly. 1.

11 m1: TTORNEY Pumas May 15, 1928.

PATENT OFFICE- AIIFBED GRA SS, 'OF NEW 1033, N. Y.

PROCESS OF MAKING PRINTING PLATES.

Application illed lay 81, 1921, Serial No. 473,782. Renewed larch18,1926.

This invention relates to the preparation of relief, intaglio orembossed letters or characters, for photographic reproduction incidentto the preparation of a zinc printing 5. plate or the like.

Prior to my invention it has been generally the custom to prepare theset-up matter for photo aphing in the. reparatlon of a zinc plate ybringing the aces-of the type or characters into a nearly perfect plane;This process has beenlmown in the industry as make-ready and has beenextremely costly and tedious. It has required an un-' usually highdegree of skill. The characters 10 which, of course, may consist ofletters, figures, geometrical designs, or the like, are first assembledin the desired relation and 1 thin strips of paper, metal, or othersuitable material are placed under such of the type or units as are tooshort to accurately reach the desired plane. When the operator believesthe type are accurately positioned in the surface plane a proof istaken. This ro'bf discloses any unevenness that may ex- 1st, and aneffort is then made to read'ust such typeas may still be short of the prnting plane. In practice thisprocedure is fre rgiently repeated againand again, and until t e proof sheet is satisfactory. The finallyaccepted proof is then photographed.

A principal'object of the invention is to.

' obviate the necessity for any make-ready and its attendant expense,and at the same time to obtain a plate sharper, clearer, and of :5 moreexact d than is' possible with the earlier descri method.

Another important object of the invention is the provision of a simplerecess for ac lishing this result whic will not recomp lo uiretbehi'degreeofskillneededintheq 8h whichwillnotrequire up matter before beingrendered ready for photographing; and

Fig. 2 is a similar view of the same after tregtment in accordance withmy invention, an

Fig. 3 is a section on the line 3--3 of Fig.

My invention contemplates the elimination of the necessity for taking aproof and the photographing in the first instance of the type set-up.Inaccordanc'e with my improved process the type is first set up inproper arrangement and allbut the type or character faces are thenrendered non-actinic so that when the (photographic exposure is made thesensitize surface receives impression only from the typefaces or exposedactinic surfaces.

This may conveniently be done by painting the entire surface of theset-up with a brush, or otherwise, and with some nonactinic substance,such as black paint, and then removing this substance, by wiping orotherwise, from the relief surfaces. Referring to the. drawing, Fig. 1shows a' type set-up, or rather a part of a type set-'up.

The built-up design consists of an assemblage of unit blockslO and 11positioned in proper relation to 'each other to form the desired design.Certain of these blocksare provided with relief or raised portions 12,the faces of which provide the printin surfaces. Fig. 2 illustrates theset-up -a er it has been treated by paintin or otherwise to.render'non-atitinic all 0 the ex sed faces except the printing surfaces0 the type or other characters.

It is believed that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the form, construction andarrangement of the parts without departing from the spirit and scope ofthe invention or sacrificing all of its material advantages,

the form hereinbefore described being merelya' referred embodimentthereof.

I c aim f 1. The process of preparing matter for photograp icreproduction incident to the preparation of a photographic plate, whichcomprises arranging the type or other characters havingportionsprojectmg above surrounding or intervening spaces and insubstantially the same plane, covering all exposed faces with anon-actinic substance, and then removing said substance from thesurfaces of the projecting portions.

2. The process of preparing matter for photograp ic reproductionincident to the preparatlon of a zinc plate, which comprises arrangingthe type or other characters having portions projecting abovesurrounding or intervening spaces and in substantially the same plane,covering all exposed faces with a non-actinic substance, and then wipingsaid substance from the surfaces of the projecting portions.

3. The rocess of preparing matter for photograp ic reproduction incidentto the preparation of a photographic plate, which comprises setting upthe type, and rovlding a non-actinic coating upon all ut the portions orfaces of the type which it is de sired to photograph.

4. The rocess of preparing matter for photographic reproduction incidentto the preparation of a zinc plate, which comprises arranging thecharacters having portions projecting above surrounding or interveningspaces and rendering all but the outer faces of said charactersnon-actinic.

5. The process of photographic reproduction incident to the preparationof a zinc plate which comprises setting up the type, rendering all butthe printing surfaces of said type non-actinic and photographing.

ALFRED GRASS.

